Method of and apparatus for distilling petroleum and the like.



L.0.SHERMAN. METHOD. OF AND APPARATUS FOR DISTILLING PETROLEUM AND THELIKE;

APPLICATION FILED APR. 24, I9I6. Z I I Patentefi Mar. 26,1918.

LG M.

INW

s I R.

LAYTON O. SHERMAN, OF EAST CHICAGO, INDIANA, ASSIGNOR TO THE CLEVELANDTRUST COMP, OF CLEVELAND, OHIO, TRUSTEE.

METHOD OF AND APPARATUS FOR DISTILLING PETROLEUM AND THE LIKE.

Specification of Letters Patent.

Patented Mar. 2%, 1918.

Application filed April 24, 1916. Serial No. 93,180.

To all whom it may concern:

. Be it known that I, LAYTON 0. SHERMAN, a citizen of the United States,residing at East Chicago, in the county of Lake and State of Indiana,have invented certain new and useful Improvements in Methods of andApparatus for Distilling Petroleum and the like, of which the followingis a specification.

This invention relates to a method of and apparatus for distilling crudeoil and the like under pressure, thereby obtaining an increased yield oflighter boiling products such as gasolene over that obtained by theusual process. It is known that the li hter the component of crude oilor petro eum the more difficult it is to crack, requiring for thispurpose a correspondingly higher pressure. Therefore in the processescommonly employed heretofore for obtaining gasolene from crudepetroleum, the latter ing fraction of oils of intermediate gravi ties,alcertain fraction or proportion of the residue containing the heaviestof the hydrocarbons is distilled under high pressure and temperature forthe purpose of cracking it into lighter hydrocarbons. Bymy process andapparatus I am able to convert into gasolene the entire range ofhydrocarbons below gasolene itself and to continuously distil directlyfrom the whole crude petroleum without separate redistillation agreaseless gasolene.

In my improved process which is performed in a single still andcondenser, after the natural light hydrocarbons or the bulk of them havebeen driven ofi, preferably at atmospheric pressure, the still is putunder pressure for the purpose of cracking the Eresidue. After thecracking temperature is ;'reached the lightest portions of thedistillate are continuously led away and condensed to form gasolene,while the balance of the distillate is continuousl condensed andsubjected under maintaine pressure to a higher temperature than that ofthe crude petroleum in the still whereby it is cracked, the crackedportions being mingled with the other cracked product comingdirectlyfrom the body of crude petroleum in the still and led to the condenserand condensed for use as gasolene.

The apparatus used is an improvement on that disclosed in my U. S.Patent No. 968,088, dated August 23, 1910.

In the accompanying drawing,-

Figure 1 is a vertical longitudinal section of the oil still, andseparator tower;

Fig. 2 is a vertical transverse section of the still on the line 1111 ofFig. 1, showing the lead false bottom, and the oil heating pipes withinthe false bottom; and

Fig. 3 is a detail showing the check valve.

The still 1, which is of the same general construction as that describedin my earlier patent, is provided with a suitable supply inlet 2, anddischarge 3, the upper portion of the still communicating, through pipe12 and perforated head 13, with a separating tower 4, shown partlybroken. This tower is divided into compartments by a series ofpartitions arranged to provide a long and tortuous vapor path, thecompartment being filled with a preferably chemically inert intothe'still and connects with a coil 7 adjacent the bottom, the other end8of the coil projecting into the space in the still above the level 9 ofthe crude oil. A check valve 25 in pipe 6 prevents back-flow from thecoil 7. Upon the bottom of the still is a mass 10 of fusible metal suchas lead, covering the coil 7, and serving as a false bottom. The stillis suitably mounted in a furnace 11 and is arranged to be heated to 900F. and above. From the tower 4c, the uncondensed vapors passby pipe 14to a condenser 15 arranged to permit condensation of the vapors undermaintained pressure, in the manner described in Patent No. 419,931, toDewar and Redwood, patented January 21, 1890. Any suitable arrangementmay be used for this purpose. I have shown one comprising the receptacle17, for the condensate, having in its up er portion or gas space, anadjustable relief valve 18. The condensate is removed from receptacle.17 by the valved pipe 19. A gas pipe 20 provided with a hand valve 21 isused for the purpose of drawing 0% the fixed gas from the apparatus andso controlling the flow of gasolene.

In the operation of the still a quantity of crude oil is run in to theproper level shown by dotted lines 9, and the furnace started. Thenatural light gasolene components are mostly distilled off atatmospheric pressure and condensed in the condenser 15. The

still is then closed by valve 23 provided in pipe let for this purpose,and the temperature and pressure in the still raised, the formerreaching 650 to 850 degrees Fahrenheit, or higher, depending upon thecrude oil used, and the latter varying from 25 pounds to 140 pounds persquare inch according to the crude oil treated, and increasing as thedistillation proceeds. As the temperature rises following the closing ofthe still there is at first simple distillation of the components ofleast gravity which condense in tower 4: and are led back through thepipes 5, and heat the same to a considerable temperature. As thecracking temperature is reached, however, the cracked products being thelightest of those given olf by the still, and comprising a certainproportion of gas, occupy the upper part of the tower and the upperpipes 5 to the exclusion of the uncracked products, the apparatus thusbecoming to an extent gas bound, which causes the upper part of thetower 4 and the upper pipes 5 to become relatively cool, which af-.

fords'a convenient method of determining by contact with said pipes whenthe operation of cracking has commenced. There upon the communication isopened to the condenser. The products of the distillation pass into thetower 4 through the pipe 12 and are condensed therein'according to theirspecific gravities or condensation points, the

heavier components of the distillate condensing in the lower portion ofthe tower and the lighter components in the upper portion of the tower;but the cracked portions of the distillate which are light enough forgasolene pass over into the condenser 15 and receiver 17. The portionsof the distillate which are too heavy to form gasolene and cannot becracked under the conditions which are most suitable for cracking theheavier Portion of the crude petroleum, but require higher temperature,

are condensed in the tower 4 as stated and pass into the pipes 5 and tothe header 6, and thence into the coil 7 submerged in the lead bottom10. Here they are immediately vaporized since the coil is maintained ata temperature.in excess of that of the body of crude petroleum andsufficient to crack these lighter hydrocarbons. Observation indicatesthat the flow through the header 6 and into the pipe 7 is notcontinuous,but that the valve 25 is normally maintained closed by the excess ofpressure in the coil 7 over that upon the columns of oil in the ,thestill and mingles with the distillate therefrom, again entering thetower 4 where the gasolene and heavier components are again separated asdescribed. Thus it will be seen that the entire process is a continuousone, the heavier components of the crude petroleum being continuouslycracked by distillation over the lead bottom and at a suitabletemperature, and the lighter components being continuously distilled andcracked in the submerged pipe beneath the surface of the lead at asuitably higher temperature, the cracked products of both distillationsbeing commingled and the gasolene separated therefrom and condensed. Thelead false bottom prevents contact of the petroleum with the bottom ofthe still where the latter is impinged upon by the hottest part of theflame, and said false bottom so distributes the heat to the petroleumthat burning by excess temperature and therefore unnecessary separationof carbon is avoided. Furthermore the carbon which separates falls uponthe surface of the molten metal and is thus prevented from accumulatingon the bottom of the still receiving the more direct impact of the heatfrom the furnace, thereby avoiding overheating in spots and removingdanger from explosions due to the h gh pressure.

Examples of the process are as follows:

A crude oil of 33 to 34$ gravity B. was distilled in the ordinary mannerto remove the light oils, until the distillate reached a gravity ofbetween 39 to 40. The residue or still bottom was now gradually raisedto a temperature of about 800 F. At about 718? F. it began to crack,making a fine light product, the pressure then being be tween 30 and 40pounds.

With a'crude oil from a different source (Cushing' crude) the resultswere as follows:

The oil had a gravity of 383 13., and was distilled without pressureuntil the gravity of its distillate was 44. Pressure was then applieduntil it reached 120 pounds, yet the temperature had reached but 715 F.,fine light products being obtained.

I claim 1. The method of obtaining gasolene and the like from crudepetroleum which comprises heating petroleum under high pressure to acracking temperature, condensing the higher boiling portions of thedistillate under pressure, heating said condensed higher boilingportions to a temperature and at a pressure above those of the initialdistillation of the crude petroleum and then passing the resultingproducts from said separately heated portions to the condenser.

2. The method of obtaining gasolene and the like from crude petroleum,which comprises heating the petroleum under high pressure to a crackingtemperature in contact with a molten difiicultly-volatile false bottom,condensing the higher boiling portions of the distillate under pressure,heating said condensed higher boiling portions to a temperature abovethat of the crude petroleum without diminution of pressure, and thenpassing the resulting products from said separately heated portions tothe condenser.

3. The method of obtaining gasolene and the like from crude petroleum,which comprises heating the petroleum under high pressure to a crackingtemperature in contact with a molten metal false bottom, condensing thehigher boiling portions of the distillate under pressure, separatelyheating said condensed higher boiling portions in a receptacle withinthe molten metal false bottom without diminution of pressure, to

a higher temperature than that of the crude petroleum in the still, andpassing the products from said separately heated portion to thecondenser.

4. The method of obtaining gasolene and the likefrom crude petroleumwhich comprises heating petroleum in a closed vessel to a crackingtemperature, condensin the higher boiling portions of the distillateunder pressure, heating said condensed higher boiling portions to atemperature and at a pressure above those of the initial distillation ofthe crude petroleum, returning the thusproduced vapors to the vaporspace in the still, and condensing the resulting products from saidseparately heated portions.

5. The method of obtaining gasolene and the like from crude petroleumwhich comprises heating petroleum ina closed vessel to a crackingtemperature, condensing the higher boiling portions of the distillateunder pressure, heating said condensed higher boiling portions in aconduit passing through molten material in the bottom portion of thestill, and returning the thus produced vapors to the vapor space in thestill, and condensing under maintained pressure the resulting productsfrom said separately heated portions.

6. The method of distilling oil which} consists in heating theoil in astill having a false bottom of molten material, condensing the higherboiling portions, reheating I the thus condensed higher boiling portionsin a conduit passing through the molten material and opening into thevapor space of the still.

7. The method of distilling oil which 'con- Y prises heating the sameunder high pressure to a temperature of between 650 F. and 850 F.,passing the vapors therefrom through a. granular inert mass, therebycondensing the higher boiling portions of the distillate and heatingsaid condensed higher boiling portions to a temperature above that ofthe crude petroleum, and then passing under maintained pressure theresulting products from said separately heated portions to thecondenser.

9. A method of obtaining gasolene and the like from crude petroleumwhich comprises heating the same under a high pressure to a temperaturebetween 650 F. and 850 F., passing the vapors therefrom through agranular inert mass, thereby condensing the higher boiling portions ofthe distillate and heating said condensed higher boiling portions to atemperature above that of the crude petroleum and then passing thevapors resulting from the. heating of the higher boiling portions of thedistillate under maintained pressure separately, heating the condensateof higher boiling point to a temperature and at a pressure above thoseof the initial distillation of the crude petroleum and returning thevapors so produced and mingling them with the vapors directly producedfrom the crude petroleum.

11. An apparatus for the distillation of petroleum consisting of astill, a fusible false bottom therein, a pipe submerged in said falsebottom, a return condenser, one end of said pipe connected to the returnpipe of the return condenser, and the other end of said pipe openinginto the vapor space of said still.

12. An apparatus for the distillation of petroleum consisting of astill, a false bottom of lead therein, a pipe submerged in the leadbottom, a return condenser, one end of said pipe connected to the returnpipe of the return condenser, the other end of said pipe unobstructedand opening into the vapor space of said still.

13. An apparatus for the distillation of petroleum consisting of astill, a false bottom of lead therein, a pipe submerged in the leadbottom, a return condenser, one end of said pipe connected to the-returnpipe of the return condenser, the other end of said' pipe unobstructedand opening into the vapor space of said still, a second condenser, anda conduit leading from the return condenser to the second condenser.

14:. An apparatus for producing gasolene from crude petroleum comprisinga still, a fused material of higher boiling point than the petroleum inthe bottom of the still, a pipe submerged in said material and extendingat one end into the upper portion of the still, a return condenser, aconnection between the return condenser and the other end of said pipe,and a check valve in said connection opening toward said pipe.

15. The method of obtaining gasolene and the like from crude petroleumwhich comprises maintaining a quiescent body of molten material in astill, heating the petroleum in contact with said body to a temperaturebetween 650 degrees F. and 850 degrees F., heating the higher boilingportion by means of said molten mass to a temperature above that of thecrude petroleum under maintained pressure, and passing the resultingproducts to a condenser.

16. The method of obtaining gasolene and the like fromcrude petroleumwhich comprises maintaining a quiescent body of molten material-in astill, heating the petroleum in contact with said body to a temperaturebetween 650 degrees F. and 850 degrees F., condensing the higher boilingportions of the distillate under pressure and heating the higher boilingportion by means of said molten mass to a temperature above that of thecrude etroleum under maintained pressure, an passing the resultingproducts to a condenser.

17. The method of obtaining gasolene and the like from crude petroleumwhich comprises heating the material under a high pressure to atemperature between 650 degrees and 850 degrees F, separating thehigher'anol the lower boiling portions of the distillate, separatelycondensing such portaeopaa tions under pressure, re-heating thecondensed higher boiling portion to a temperature above that of thecrude petroleum, sepa rating the products resulting from said reheatinginto a higher and a lower boiling portion, separately condensing thehigher boiling portion and re-heating it at a temperature above that ofthe crude petroleum.

18. The method of obtaining gasolene and the like from crude petroleumwhich comprises heating the material under high pressure to a crackingtemperature, condensing the higher boiling portions of the distillate,returning the resulting condensate to the same still, heating it thereinto a higher temperature than that of the liquid body of petroleum in thestill and thereby vaporizing and further cracking said condensate andpassing the light products from the crude petroleum and from thecondensate together to a condenser.

19. The method of obtaining gasolene and the like from crude petroleumwhich comprises heating the material in a liquid body to a crackingtemperature under high pressure, passing the vapors therefrom through acondenser which condenses the heavier hydrocarbons in the distillate,passing the lighter hydrocarbons in the distillate to a secondcondenser, returning the heavier portions of the distillate to thestill, heating them in said still while separate from the crudepetroleum to a higher temperature than-that of the latter, therebyvaporizing and partially cracking the same, and mixing the vapors withthe vapors from the crude petroleum.

20. Apparatus for distilling petroleum, comprising a still, asuperheating-coil of considerable heating-surface in said still beneaththe surface of the oil and having one end open to the vapor-space in thestill, a return-condenser, means for conveying the vapors from saidstillto said return-condenser, a condenser connected to the upper part of thereturn-condenser, conduits connecting said return-condenser at variousheights thereof to the other end of said superheatingcoil and means forpreventing back-flow toward the return-condenser.

- LAYTON O. SHERMAN.

